Rack information handling system having modular liquid distribution (mld) conduits

ABSTRACT

A direct-interface liquid-cooled (DL) Rack Information Handling System (RIHS) includes liquid cooled (LC) nodes each comprising a chassis received in a respective chassis-receiving bay of a rack and containing heat-generating functional components. Each LC node is configured with a system of conduits to receive direct injection of cooling liquid to regulate the ambient temperature of the node and provide cooling to the functional components inside the node by removing heat generated by the heat-generating functional components. A cooling subsystem has a liquid rail formed by more than one node-to-node, Modular Liquid Distribution (MLD) conduits, each including first and second terminal connections attached on opposite ends of a central conduit that can be rack-unit dimensioned. The MLD conduits seal to and enable fluid transfer between a port of a selected LC node and a port of an adjacent LC node.

PRIORITY

The present invention claims priority from Provisional Application Ser.No. 62/270,563, with filing/priority date of Dec. 21, 2015. The entirecontent of the provisional application is incorporated herein byreference.

BACKGROUND

1. Technical Field

The present disclosure generally relates to information handling systems(IHS), and more particular to a rack-configured IHS, having a liquidcooling subsystem and liquid-cooled nodes. Still more particularly, thedisclosure is related to a liquid cooling system having a modular rackliquid distribution network of conduits.

2. Description of the Related Art

As the value and use of information continue to increase, individualsand businesses seek additional ways to process and store information.One option available to users is Information Handling Systems (IHSs). AnIHS generally processes, compiles, stores, and/or communicatesinformation or data for business, personal, or other purposes, therebyallowing users to take advantage of the value of the information.Because technology and information handling needs and requirements varybetween different users or applications, IHSs may also vary regardingwhat information is handled, how the information is handled, how muchinformation is processed, stored, or communicated, and how quickly andefficiently the information may be processed, stored, or communicated.The variations in IHSs allow for IHSs to be general or configured for aspecific user or specific use such as financial transaction processing,airline reservations, enterprise data storage, or global communications.In addition, IHSs may include a variety of hardware and softwarecomponents that may be configured to process, store, and communicateinformation and may include one or more computer systems, data storagesystems, and networking systems.

For implementations requiring a large amount of processing capability, arack-configured (or rack) IHS (RIHS) can be provided. The RIHS includesa physical rack, within which is inserted a plurality of functionalnodes, such as server (or processing) nodes/modules, storage nodes, andpower supply nodes. These nodes, and particularly the server nodes,typically include processors and other functional components thatdissipate heat when operating and/or when connected to a power supply.Efficient removal of the heat being generated by these components isrequired to maintain the operational integrity of the RIHS. Traditionalheat removal systems include use of air movers, such as fans, toconvectionally transfer the heat from inside of the RIHS to outside theRIHS. More recently, some RIHS have been designed to enable submersionof the server modules and/or the heat generating components in a tank ofcooling liquid to effect cooling via absorption of the heat by thesurrounding immersion liquid.

The amount of processing capacity and storage capacity per node and/orper rack continues to increase, providing greater heat dissipation pernode and requiring more directed cooling solutions. Thus, there is acontinuing need for further innovations to provide directed cooling forthe individual heat generating components, both at the individual nodelevel, as well as at the larger rack level. When designing the coolingsubsystem, consideration must also be given to the different formfactors of IT nodes and rack heights of the RIHS, and the ability toeffectively control cooling discretely (at device or node level) andgenerally across the overall RIHS.

As liquid cooling improves in efficiencies and performance, data centersolutions continue to focus on implementing liquid cooling at the racklevel. Recently, localized liquid solutions (CPU/GPU cold plates) havebeen successful in removing most of the heat from these componentswithin a server and into the facility cooling loop through directfluid-to-fluid heat exchangers (server cooling loop to facility coolingloop) within the rack, but this method does not provide cooling toauxiliary components (such as storage devices (HDDs, memory), orcritical secondary ICT equipment, such as top of the rack switch,network switches, battery backup units, or Power Supply Units (PSUs).

BRIEF SUMMARY

The illustrative embodiments of the present disclosure provides aDirect-Interface Liquid-Cooled (DL) Rack Information Handling System(RIHS), a direct-interface liquid cooling subsystem, and a method formodularly providing liquid cooling to information technology (IT) nodeswithin a RIHS. The IT nodes are liquid cooled (LC) nodes that containheat-generating functional components, and the nodes can have differentform factors and different cooling requirements. In one or moreembodiments, the RIHS includes a rack having chassis-receiving bays.Each chassis is received into a respective chassis-receiving bay of therack. The chassis can be a node enclosure or can be a block chassis thatreceives more than one node enclosure. Each LC node is configured with asystem of conduits to receive direct injection of cooling liquid toregulate the ambient temperature of the node and provide cooling to thecomponents inside the node by absorbing and removing heat generated bythe heat-generating functional components. The cooling subsystem has aliquid rail formed by more than one node-to-node, Modular LiquidDistribution (MLD) conduits connecting between LC nodes provisioned inthe rack. The MLD conduits comprise first and second terminalconnections attached on opposite ends of a central conduit that israck-unit dimensioned to seal to and enable fluid transfer between aport of a selected LC node and a port of an adjacent LC node.

According to at least one aspect of the present disclosure, a liquidcooling subsystem of a RIHS includes a liquid rail formed by more thanone node-to-node, MLD conduits connecting between more than one LC nodeprovisioned in a rack. Each LC node includes a chassis received in arespective chassis-receiving bay of the rack and each LC node containsone or more heat-generating functional components. Each LC node isconfigured with a system of conduits to receive direct injection ofcooling liquid to regulate the ambient temperature of the node andprovide cooling to the components inside the node by absorbing andremoving heat generated by the heat-generating functional components.

According to at least one aspect of the present disclosure, a method isprovided of assembling a DL RIHS that includes mounting a plurality ofblock liquid manifolds at a back of the rack, where each block liquidmanifold has at least one rail supply port and a rail return port on anoutside facing side of the block liquid manifold that respectivelycommunicate with at least one block supply port and a block return porton an inside facing side of the block liquid manifold. The methodincludes inserting more than one LC nodes in receiving bays of the rackcorresponding to locations of the mounted block liquid manifolds, withthe supply ports and the return ports of the LC nodes and an insidefacing portion of the corresponding block liquid manifold linearlyaligned. The method includes sealing, for fluid transfer, the ports of aselected one or more LC nodes to the lineally aligned block supply andreturn ports of the inside facing portion of the block liquid manifold.The method includes attaching node-to-node interconnecting ModularLiquid Distribution (MLD) conduits between a selected pair of adjacentrail supply ports and adjacent rail return ports of the exterior face ofthe block liquid manifolds to form a supply conduit and a returnconduit, respectively, of a scalable liquid rail. The method furtherincludes attaching bypass conduits across the nodes to allow forcontinued flow of cooling liquid to the remaining nodes in the RIHSfollowing removal of one or more of the MLD conduits serving specificnodes. The assembly enables liquid cooling to the functional componentsinside the LC nodes. Liquid cooling is provided to the functionalcomponents inside the LC nodes via liquid absorption of heat generatedby the heat-generating functional components, followed by liquidtransfer of the absorbed heat away from the inside of the node.

The above presents a general summary of several aspects of thedisclosure in order to provide a basic understanding of at least someaspects of the disclosure. The above summary contains simplifications,generalizations and omissions of detail and is not intended as acomprehensive description of the claimed subject matter but, rather, isintended to provide a brief overview of some of the functionalityassociated therewith. The summary is not intended to delineate the scopeof the claims, and the summary merely presents some concepts of thedisclosure in a general form as a prelude to the more detaileddescription that follows. Other systems, methods, functionality,features and advantages of the claimed subject matter will be or willbecome apparent to one with skill in the art upon examination of thefollowing figures and detailed written description.

BRIEF DESCRIPTION OF THE DRAWINGS

The description of the illustrative embodiments can be read inconjunction with the accompanying figures. It will be appreciated thatfor simplicity and clarity of illustration, elements illustrated in thefigures have not necessarily been drawn to scale. For example, thedimensions of some of the elements are exaggerated relative to otherelements. Embodiments incorporating teachings of the present disclosureare shown and described with respect to the figures presented herein, inwhich:

FIG. 1 illustrates a side perspective view of an internallayout/configuration of an example Direct-Interface Liquid-Cooled (DL)RIHS, according to one or more embodiments;

FIG. 2 illustrates a top view of an example LC node configured with aliquid cooling subsystem that includes a liquid-to-liquid manifold andcooling pipes for conductively cooling internal functional components,according to one or more embodiments;

FIG. 3 illustrates a rear perspective view of an example DL RIHS with alouvered rear door in a closed position over uncovered MLD conduits,according to one or more embodiments;

FIGS. 4 and 5 illustrate a rear perspective view of the example DL RIHSof FIG. 3 with the louvered rear door opened to expose node-to-nodeinterconnection of MLD conduits of different vertical sizes havingappropriately sized and removable pipe covers, according to one or moreembodiments;

FIG. 6 illustrates the rear perspective view of FIGS. 4-5 with the pipecovers removed to expose the MLD conduits, according to one or moreembodiments;

FIG. 7 illustrates a rear perspective view of an example RIHS with MLDconduits in fluid communication with supply side conduits extending froma top of the rack, according to one or more embodiments;

FIG. 8 illustrates a detailed block diagram of a DL RIHS configured withLC nodes arranged in blocks and which are cooled in part by a liquidcooling system having a rail comprised of MLD conduits, and in part by asubsystem of air-liquid heat exchangers, according to multipleembodiments;

FIG. 9A illustrates an expanded, more detailed view of the liquidinterconnection between the node level heat exchange manifold, the blockliquid manifold containing the air-liquid heat exchanger, and exampleMLDs of the liquid rail, according to multiple embodiments;

FIG. 9B illustrates a functional block diagram of an example DL RIHShaving three LC nodes cooled by a liquid rail of MLD conduits and supplyand return divert conduits, according to one or more embodiments;

FIG. 9C illustrates a functional block diagram of the example DL RIHS ofFIG. 9B having an LC node removed, according to one or more embodiments;

FIG. 9D illustrates a functional block diagram of the example of DL RIHSof FIG. 9B with a supply and a return MLD conduit removed, according toone or more embodiments;

FIG. 9E illustrates a functional block diagram of the example of DL RIHSof FIG. 9B with a block chassis and LC node removed, according to one ormore embodiments;

FIG. 10 illustrates a perspective view of a portion of a DL RIHSdepicting example nodes, block radiators with Air-Liquid heatexchangers, and MLD conduits, according to one or more embodiments;

FIG. 11 illustrates a rear perspective view of the example RIHS of FIG.5 with an exploded detail view of MLD conduits, according to one or moreembodiments;

FIG. 12 illustrates a rear perspective view of the example RIHS of FIG.5 with an exploded detail view of example bottom-feed facility supplyconduits and return MLD conduits, according to one or more embodiments;

FIG. 13A illustrates a top view of a rack filtration unit (RFU) of theexample cooling subsystem, according to one or more embodiments;

FIG. 13B illustrates a bottom view of the RFU of the example coolingsubsystem of FIG. 13A, according to one or more embodiments;

FIG. 14 illustrates a flow diagram of a method of assembling a DL RIHSusing MLD conduits, according to one or more embodiments; and

FIG. 15 illustrates a flow diagram of a method of using a liquid rackfor Direct-interface liquid cooling of the DL RIHS, according to one ormore embodiments.

DETAILED DESCRIPTION

The present disclosure generally provides a Direct-InterfaceLiquid-Cooled (DL) Rack Information Handling System (RIHS) providingliquid cooled (LC) information technology (IT) nodes containingheat-generating functional components and which are cooled at least inpart by a liquid cooling subsystem. The RIHS includes a rack configuredwith chassis-receiving bays in which is received a respective chassis ofone of the LC nodes. Each LC node is configured with a system ofconduits to receive direct injection of cooling liquid to regulate theambient temperature of the node. Additionally, each LC node, configuredwith a system of conduits, provides cooling to the components inside thenode by conductively absorbing, via the cooling liquid, heat generatedby the heat-generating functional components. The absorbed heat isremoved (or transferred away) from within the node to outside of thenode and/or the RIHS. The cooling subsystem has a liquid rail formed bymore than one node-to-node, Modular Liquid Distribution (MLD) conduit,which include first and second terminal connections attached on oppositeends of a central conduit. The MLD conduits are rack-unit dimensioned toseal to and enable fluid transfer between a port of a selected LC nodeand a port of an adjacent LC node.

In the following detailed description of exemplary embodiments of thedisclosure, specific exemplary embodiments in which the disclosure maybe practiced are described in sufficient detail to enable those skilledin the art to practice the disclosed embodiments. For example, specificdetails such as specific method orders, structures, elements, andconnections have been presented herein. However, it is to be understoodthat the specific details presented need not be utilized to practiceembodiments of the present disclosure. It is also to be understood thatother embodiments may be utilized and that logical, architectural,programmatic, mechanical, electrical and other changes may be madewithout departing from general scope of the disclosure. The followingdetailed description is, therefore, not to be taken in a limiting sense,and the scope of the present disclosure is defined by the appendedclaims and equivalents thereof.

References within the specification to “one embodiment,” “anembodiment,” “embodiments”, or “one or more embodiments” are intended toindicate that a particular feature, structure, or characteristicdescribed in connection with the embodiment is included in at least oneembodiment of the present disclosure. The appearance of such phrases invarious places within the specification are not necessarily allreferring to the same embodiment, nor are separate or alternativeembodiments mutually exclusive of other embodiments. Further, variousfeatures are described which may be exhibited by some embodiments andnot by others. Similarly, various requirements are described which maybe requirements for some embodiments but not other embodiments.

It is understood that the use of specific component, device and/orparameter names and/or corresponding acronyms thereof, such as those ofthe executing utility, logic, and/or firmware described herein, are forexample only and not meant to imply any limitations on the describedembodiments. The embodiments may thus be described with differentnomenclature and/or terminology utilized to describe the components,devices, parameters, methods and/or functions herein, withoutlimitation. References to any specific protocol or proprietary name indescribing one or more elements, features or concepts of the embodimentsare provided solely as examples of one implementation, and suchreferences do not limit the extension of the claimed embodiments toembodiments in which different element, feature, protocol, or conceptnames are utilized. Thus, each term utilized herein is to be given itsbroadest interpretation given the context in which that terms isutilized.

As utilized herein, the term “rack-configured” (as in RIHS) generallyrefers to the configuration of a large scale sever system within aphysical rack having multiple chassis receiving rails for receivingspecific sizes of information technology (IT) nodes, such as servermodules, storage modules, and power modules. The term node generallyrefers to each separate unit inserted into a 1U or other height rackspace within the rack. In one embodiment, operational characteristics ofthe various IT nodes can be collectively controlled by a singlerack-level controller. However, in the illustrated embodiments, multiplenodes can be arranged into blocks, with each block having a separateblock-level controller that is communicatively connected to therack-level controller.

For purposes of this disclosure, an information handling system (definedat the individual server level) may include any instrumentality oraggregate of instrumentalities operable to compute, classify, process,transmit, receive, retrieve, originate, switch, store, display,manifest, detect, record, reproduce, handle, or utilize any form ofinformation, intelligence, or data for business, scientific, control, orother purposes. For example, an information handling system may be apersonal computer, a network storage device, or any other suitabledevice and may vary in size, shape, performance, functionality, andprice. The information handling system may include random access memory(RAM), one or more processing resources such as a central processingunit (CPU) or hardware or software control logic, ROM, and/or othertypes of nonvolatile memory. Additional components of the informationhandling system may include one or more disk drives, one or more networkports for communication with external devices as well as various inputand output (I/O) devices, such as a keyboard, a mouse, and a videodisplay. The information handling system may also include one or morebuses operable to transmit communications between the various hardwarecomponents.

As illustrated by the figures and described herein, multiple processingservers or server IHSs (referred to herein as server nodes) can beincluded within the single RIHS. Certain aspect of the disclosure thenrelate to the specific LC (sever or other) nodes and the functionalityassociated with these individual nodes or block-level groupings ofnodes, while other aspects more generally relate to the overall DL RIHScontaining all of the LC nodes.

As one design detail/aspect for the present innovation, consideration isgiven to the fact that extreme variations can exist inserver/power/network topology configurations within an IT rack. Inaddition to dimension variations, the thermal requirements forheat-generating functional components for power, control, storage andserver nodes can be very different between types or vary according tousage. These variations drive corresponding extreme diversity in portplacement, fitting size requirements, mounting locations, and manifoldcapacity for a liquid cooling subsystem. Further, a chassis of each nodeis typically densely provisioned. Lack of space thus exists to mount adiscrete water distribution manifold in high-power IT racks. The presentdisclosure addresses and overcomes the challenges with distributingliquid cooling fluids throughout an IT rack having nodes with a largenumber of variations in distribution components.

The disclosure also includes the additional consideration that inaddition to cooling the primary heat generating components of the rack,such as the processor, what is needed is a way to allow for cooling ofsecondary equipment within the rack, as well as auxiliary componentsthat would further support utilizing the advantages of a fluid-to-fluidheat exchanger methodology. Additionally, the present disclosureprovides a modular approach to utilizing an air-to-liquid heat exchangerwith quick connection and scalability to allow the solution to bescalable in both 1U and 2U increments.

FIG. 1 illustrates a side perspective view of an internallayout/configuration of an example Direct-Interface Liquid-Cooled (DL)RIHS 100 configured with a plurality of LC nodes 102, according to oneor more embodiments. For simplicity, the example DL RIHS presented inthe various illustrations can be described herein as simply RIHS 100;however, references to RIHS 100 are understood to refer to a DL RIHS,with the associated liquid cooling infrastructure and/or subsystems andsupported LC nodes 102. RIHS 100 includes rack 104, which comprises arack frame and side panels, creating a front-to-back cabinet withinwhich a plurality of chassis receiving bays are vertically arranged andin which a chassis of a respective IT node 102 can be inserted. Rack 104includes certain physical support structures (not specifically shown)that support IT gear insertion at each node location. Additionaldescription of the structural make-up of an example rack is provided inthe description of FIGS. 2-4, which follows.

FIG. 1 depicts an illustrative example of LC nodes 102 a-102 j(collectively refer to as nodes 102), with each nodes 102 a-102 iincluding heat-generating functional components 106. Additionally, RIHS100 also includes an infrastructure node 102 j and liquid filtrationnode 102 k, which do not necessarily include heat-generating functionalcomponents 106 that require liquid cooling, as the other LC nodes 102a-102 i. In the illustrative embodiments, nodes 102 a-102 b, and 102e-102 h include other components 108 that are not necessarily heatgenerating, but which are exposed to the same ambient heat conditions asthe heat generating components by virtue of their location within thenode. In one embodiment, these other components 108 can be sufficientlycooled by the direct injection of cooling liquid applied to the nodeand/or using forced or convective air movement, as described laterherein. Each node 102 is supported and protected by a respective nodeenclosure 107. Nodes 102 a-102 d are further received in node receivingbays 109 of a first block chassis 110 a of a first block 112 a. Nodes102 e-102 i are received in a second block chassis 110 of a second block112 b. In the illustrative embodiments, the nodes 102 are verticallyarranged. In one or more alternate embodiments, at least portions of thenodes 102 (and potentially all of the nodes) may also be arrangedhorizontally while benefiting from aspects of the present innovation.

The present innovation is not limited to any specific number orconfiguration of nodes 102 or blocks 112 in a rack 104. According to oneaspect, nodes 102 can be of different physical heights of form factors(e.g., 1U, 1.5U, 2U), and the described features can also be applied tonodes 102 having different widths and depths (into the rack), with someextensions made and/or lateral modifications to the placement of coolingsubsystem conduits, as needed to accommodate the different physicaldimensions. As a specific example, node 102 i is depicted as having alarger node enclosure 107′ (with corresponding different dimensions ofheat-generating functional components 106′) of a different number ofrack units in physical height (e.g., 2U) that differs from the heights(e.g., 1U) of the other nodes 102 a-102 h and 102 j-102 k. RIHS 100 caninclude blocks 112 or nodes 102 selectably of a range of discrete rackunits. Also, different types of IT components can be provided withineach node 102, with each node possibly performing different functionswithin RIHS 100. Thus, for example, a given node 102 may include one ofa server module, a power module, a control module, or a storage module.In a simplest configuration, the nodes 102 can be individual nodesoperating independent of each other, with the RIHS 100 including atleast one rack-level controller (RC) 116 for controlling operationalconditions within the RIHS 100, such as temperature, power consumption,communication, and the like. Each node 102 is then equipped with anode-level controller (NC) 118 that communicates with the rack-levelcontroller 116 to provide localized control of the operationalconditions of the node 102. In the more standard configuration of a DLRIHS 100, and in line with the described embodiments, RIHS 100 alsoincludes block-level controllers (BCs) 114, communicatively coupled tothe rack-level controller 116 and performing block-level controlfunctions for the LC nodes within the specific block. In thisconfiguration, the nodes 102 are arranged into blocks 112, with eachblock 112 having one or more nodes 102 and a corresponding block-levelcontroller 114. Note the blocks do not necessarily include the samenumber of nodes, and a block can include a single node, in someimplementations.

A Direct-Interface Liquid Cooling (DL) subsystem (generally shown asbeing within the RIHS and labelled herein as 120) provides liquidcooling to heat-generating functional components 106 via a liquid rail124 under the control of the rack-level controller 116, block-levelcontrollers 114, and/or node-level controllers 118, in some embodiments.Rack-level controller 116 controls a supply valve 126, such as asolenoid valve, to allow cooling liquid, such as water, to be receivedfrom a facility supply 128. The cooling liquid is received from facilitysupply 128 and is passed through liquid filtration node 102 l beforebeing passed through supply conduit 130 of liquid rail 124. Each block112 a, 112 b receives a dynamically controlled amount of the coolingliquid via block-level dynamic control valve 132, such as a proportionalvalve. Return flow from each block 112 a, 112 b can be protected frombackflow by a block check valve 133. The individual needs of therespective nodes 102 a-102 d of block 112 a can be dynamically providedby respective node-level dynamic control valves 134, controlled by theblock-level controller 114, which control can, in some embodiments, befacilitated by the node-level controllers 118. In addition to allocatingcooling liquid in accordance with cooling requirements (which can beoptimized for considerations such as performance and economy), each ofthe supply valve 126 and/or dynamic control valves 132, 134 can beindividually closed to mitigate a leak. A check valve 136 is providedbetween each node 102 a-102 j and a return conduit 138 of the liquidrail 124 to prevent a backflow into the nodes 102 a-102 j. The returnconduit 138 returns the cooling liquid to a facility return 140.

To support the temperature control aspects of the overall system, RIHS100 includes temperature sensors 101 that are each located within orproximate to each node 102 a-102 j, with each gauge 101 connected to thenode-level controller 118 and/or the corresponding block-levelcontroller 114. Temperature sensors 101 operate in a feedback controlloop of the liquid cooling system 122 to control the amount of liquidflow required to cool the nodes 102 a-102 j. In one or more embodiments,the rack-level controller 116 can coordinate performance constraints toblock-level controllers 114 and/or node-level controllers 118 that limitan amount of heat generated by the heat-generating functional components106 to match a heat capacity of the flow of cooling liquid in DLsubsystem 122. Alternatively or in addition, the rack-level controller116 can coordinate cooling levels to block-level controllers 114 and/ornode-level controllers 118 that in turn control the dynamic controlvalves 132, 134 for absorption and transfer of the heat generated by theheat-generating functional components 106 by the DL subsystem 122. Inone or more embodiments, support controllers such as a Rack LiquidInfrastructure Controller (RLIC) 142 can perform management andoperational testing of DL subsystem 122. RLIC 142 can monitor pressuresensors 144 and liquid sensors 146 to detect a leak, to validateoperation of a namic control valves 132, 134 or shut-off valves such assupply valve 126. RLIC 142 can perform close-loop control of specificflow rates within the RIHS 100.

FIG. 2 illustrates example LC node 200 of example DL RIHS 100 of FIG. 1having a node enclosure 208 insertable into a block chassis 210. Forpurposes of description, node 200 is a server IHS that includesprocessing components or central processing units (CPUs), storagedevices, and other components. LC node 200 includes cooling subsystem(generally shown and represented as 220) that includes aliquid-to-liquid manifold 242 to cool heat-generating functionalcomponents 206 by heat transfer from liquid provided by node-levelsupply conduit 244, and return conduit 246, according to one or moreembodiments. Node-level supply conduit 244 and return conduit 246 areappropriately sized and architecturally placed relative to the othercomponents and the dimensionality (i.e., width, height, anddepth/length) of LC node 200 to permit sufficient cooling liquid to passthrough the interior of LC the node 200 to remove the required amount ofheat from LC node 200 in order to provide appropriate operatingconditions (in terms of temperature) for the functional componentslocated within LC node 200. Liquid-to-liquid manifold 242 can includeCPU cold plates 248 and voltage regulator cold plates 250. A sledassembly grab handle 252 can be attached between CPU cold plates 248 forlifting LC node 200 out of block chassis 210. A return-side check valve254 of the return conduit 246 can prevent facility water fromback-feeding into LC node 200 such as during a leak event. Flex hoselinks 256 in each of node-level supply conduit 244 and return conduits246 can reduce insertion force for sleds into block chassis 210. Sledemergency shutoff device 234 interposed in the supply conduit 244 can bea solenoid valve that closes in response to input from a hardwarecircuit during a sled-level leak detection event. Node-level carrier 258received in node enclosure 208 can incorporate liquid containmentstructure 260 to protect storage device 262. In the illustrative exampleillustrated by FIG. 2, LC node 200 is oriented horizontally and isviewed from above. In one or more embodiments node-level carrier 258 isconfigured to route leaked cooling liquid away from storage device 262when oriented vertically.

FIGS. 3-7 illustrate different exterior and rear views of an exampleassembled DL RIHS 300. DL RIHS 300 includes rack 304, which is aphysical support structure having an exterior frame and attached sidepanels to create cabinet enclosure 364 providing interior chassisreceiving bays (not shown) within which a plurality of individual nodechasses (or sleds) 208 of functional IT nodes, such as LC node 200 ofFIG. 2, are received. In the description of the figures, similarfeatures introduced in an earlier figure are not necessarily describedagain in the description of the later figures.

FIGS. 3-5 specifically illustrate exterior views of rack 304 of exampleDL RIHS 100. As illustrated, rack 304 includes opposing side panels 366,attached to a top panel 368 (and bottom panel—not shown) to create themain cabinet enclosure 364 that includes multiple chassis receiving baysfor housing LC nodes 102/200. The created cabinet enclosure 364 includesa front access side (not shown) and a rear side. The front access sideprovides access to the chassis receiving bays created within the maincabinet enclosure 364 for receiving LC nodes 102 (of FIG. 1) into rack304. Attached to the rear ends of the main opposing side panels 366 areopposing side panel extensions 372. A louvered rear door 374 is hinged(or otherwise attached) to one of the side panel extensions 372 andincludes a latching mechanism for holding the door 374 in a closedposition, where in a closed position is relative to the otherwise openspace extending laterally between opposing side panel extensions 372.Side panel extensions 372 and louvered rear door 374 provide anextension to main cabinet enclosure 364 for housing,covering/protecting, and providing access to the modular, scalableliquid rail 324 of a liquid cooling subsystem 322 that provides liquidcooling to each LC node 102 (of FIG. 1) inserted into the chassis of themain cabinet enclosure 364.

FIG. 4 illustrates an embodiment in which rear pipe covers 476 canprotect portions of liquid rail 324 (of FIG. 3), and specificallyModular Liquid Distribution (MLD) conduits 478, from inadvertent damageas well as containing any leaks from being directed at sensitivefunctional components 106 (of FIG. 1).

Illustrated in FIG. 5 are rear pipe covers 476 (of FIG. 4) of MLDconduits 478 (of FIG. 4) of liquid rail 324 (of FIG. 3) having differentsizes. According to one aspect, the MLD conduits 478 (of FIG. 4) arerack unit dimensioned pipes that form a node-to-node scalable rackliquid manifold (“liquid rail”) to distribute cooling liquid, asrequired, for each node 102 (of FIG. 1) and through the verticalarrangement of nodes 102 (of FIG. 1) within RIHS 100 (of FIG. 1). In anexemplary embodiment, the cooling liquid is received from a facilitysupply 128 (of FIG. 1) via below rack (e.g. ground level or below floor)connections 580.

FIG. 6 illustrates an example RIHS 100, as depicted in FIG. 1, with MLDconduits 478 (of FIG. 4), that are uncovered, displaying liquid rail 324(of FIG. 3). In the embodiment of FIG. 6, cooling liquid is receivedfrom a facility supply 128 (FIG. 1) by below rack (e.g. ground level orbelow floor) connections 680.

FIG. 7 illustrates a second example RIHS 700, wherein cooling liquid isreceived from facility supply 128 (FIG. 1) provided by an above-rack(and possibly in ceiling) connections 780. Also shown by FIG. 7 are airmovers depicted as fan modules 782 adjacent to the liquid rail. Thesefan modules 782 are mounted at the back of RIHS 700 to draw air flowthrough LC nodes 102 providing additional cooling of LC nodes 102, ofFIG. 1, (e.g., convection cooling for node components 106, of FIG. 1)that may or may not also receive direct-interface of cooling liquid, indifferent embodiments.

FIG. 8 illustrates a more detailed view of the interconnections of theliquid cooling subsystem, at a node level and rack level within anexample DL RIHS 800. As shown, RIHS 800 is configured with LC nodes 802a-802 e arranged in blocks (e.g., block 1 comprising 802 a-802 c) andwhich are cooled in part by a liquid cooling system having a liquid railcomprised of MLD conduits, and in part by a subsystem of air-liquid heatexchangers, can be configured with heat-generating functional components806 and that are cooled at least in part by a system of MLD conduits 878a-878 b, according to one or more embodiments. Illustrated within nodes802 are heat-generating functional components 806, such as processors,voltage regulators, etc., which emit heat during operation and or whenpower is applied to the component, such that the ambient temperatureincreases around the component, and within the node, and eventuallywithin the block, and ultimately DL RIHS 800, during standard operation.To mitigate heat dissipation (and effects thereof), and to maintain theRIHS, block, node, and functional components within proper operatingtemperatures, DL RIHS 800 is configured with a DL subsystem 822. DLsubsystem 822 includes a rack level network of liquid propagating pipes,or conduits that are in fluid communication with individual node levelnetworks of liquid propagating conduits. Additionally, DL subsystem 822collectively facilitates heat absorption and removal at the componentlevel, the node level, the block level, and/or the rack level. Therack-level network of conduits includes a modular arrangement of aliquid rail 824 formed by more than one node-to-node MLD conduit 878a-878 b spanning (or extending) between LC nodes 802 provisioned in rack804.

At the top position of RIHS 800, a block chassis 810 is received in ablock chassis receiving bay 870 a of rack 804. Within block chassis 810,a first node 802 a received in a first node receiving bay 809 a of therack 804 has a vertical height of one rack unit (1U). A rack unit, U orRU as a unit of measure, describes the height of electronic equipmentdesigned to mount in a 19-inch rack or a 13-inch rack. The 19 inches(482.60 mm) or 13 inches (584.20 mm) dimension reflects the horizontallateral width of the equipment mounting-frame in the rack including theframe; the width of the equipment that can be mounted inside the rack isless. According to current convention, one rack unit is 1.75 inches(44.45 mm) high. A second node 802 b received in a second node receivingbay 809 b of the rack 104 (of FIG. 1) has a vertical height of 1U. Athird node 802 c received in a third node receiving bay 809 c of therack 804 has a vertical height of 1U. A fourth node 802 d,infrastructure node 802 b, is received in a second block chassisreceiving bay 870 b of rack 804 and has a vertical height of 1U.Infrastructure node 802 b can contain functional components such as arack-level controller 816. A fifth node 802 e is received in a thirdchassis receiving bay 870 c and has a vertical height of 2U. A sixthnode 802 f, which provides a Rack Filtration Unit (RFU) 871, is receivedin a fourth block chassis receiving bay 870 d of the rack 804.Infrastructure node 802 and RFU 871 are examples of nodes 802 that maynot require liquid cooling. A cascading liquid containment unit 890 isreceived in a fifth chassis receiving bay 870 e and includes liquidsensor 897.

MLD conduits 878 a of 1U can be used to connect nodes of 1U verticalspacing. Because of the additional 1U separation of LC nodes 802 c and802 e by inclusion of infrastructure node 802 d, MLD conduit 878 bbetween the third and fifth nodes 802 c-802 d is dimension 2U toaccommodate the increased spacing. MLD conduits 878 a-878 b can thussupport different heights (1U to NU) of IT components.

Each MLD conduit 878 a-878 b includes first and second terminalconnections 883, 884 attached on opposite ends of central conduit 885that is rack-unit dimensioned to seal to a port of LC node 802 andenable fluid transfer between a port of a selected LC node 802 and aport of an adjacent LC node 802. In FIG. 8, facility supply 828 andfacility return 840 are respectively located at the intake end of liquidrail 824 and the exhaust end of liquid rail 824. The actual location offacility supply 828 and facility return 840 can be reversed.Alternatively, facility supply 828 and facility return 840 can belocated above the RIHS 800 or both conduits can be located on oppositesides of the RIHS 800 in alternate embodiments.

Liquid cooling subsystem 822 includes a liquid infrastructure managercontroller (LIMC) 886 which is communicatively coupled to block liquidcontrollers (BLCs) 887 to collectively control the amount of coolingliquid that flows through the RIHS 800 and ultimately through each ofthe nodes 802 in order to effect a desired amount of liquid cooling atthe component level, node level, block level, and rack level. Forclarity, LIMC 886 and BLCs 887 are depicted as separate components. Inone or more embodiments, the liquid control features of the LIMC 886 andBLCs 887 can be incorporated into one or more of the rack-levelcontroller 816, block-level controllers 820, and the node-levelcontrollers 818. As illustrated in FIG. 1 and previously described, eachof the LIMC 886 and BLCs 887 are connected to and respectively controlthe opening and closing of flow control valves that determine the amountof flow rate applied to each block and to each node within the specificblock. During cooling operations, one of LIMC 886 and BLC 887 causes aspecific amount of liquid to be directly injected into the intakeconduits of the LC node 802, which forces the cooling liquid through thesystem of conduits within the LC node 802 to the relevant areas and/orfunctional components/devices inside the nodes 802 to absorb and removeheat away from the inside of the node and/or from around the componentswithin the node.

As another aspect, the present disclosure provides a modular approach toutilizing air-to-liquid heat exchanger 888 with quick connection and isscalable in both 1U and 2U increments. In one or more embodiments, DLcooling subsystem 822 can include a plurality of air-to-liquid (orliquid-to-air) heat exchangers 888 that facilitate the release of someof the heat absorbed by the exhaust liquid to the surrounding atmospherearound the RIHS 100 (of FIG. 1). Air-to-liquid heat exchangers 888 canbe integral to block liquid manifold 889 that, along with the MLDconduits 878 a-878 b, form scalable liquid rail 824. One aspect of thepresent disclosure is directed to providing scalable rack-mountedair-to-liquid heat exchanger 888 for targeted heat rejection ofrack-mounted equipment to DL cooling subsystem 822. Hot air 899 fromauxiliary components, such as storage device 895, would be pushedthrough the air-to-liquid heat exchanger 888, and the resulting energywould transfer to liquid rail 824 and be rejected to a facility coolingloop, represented by the facility return 840.

RIHS 800 can include variations in LC node 802 that still maintainuniformity in interconnections along liquid rail 824 formed by achassis-to-chassis modular interconnect system of MLD conduits 878 a-878b. With this scalability feature accomplished using MLD conduits 878a-878 b, cooling subsystem 822 of the RIHS 800 allows each block chassis810 to be a section of a scalable manifold, referred herein as liquidrail 824, eliminating the need for a rack manifold. The scalability ofliquid rail 824 enables flexible configurations to include variouspermutations of server and switch gear within the same rack (rack 804).MLD conduits 878 a-878 b can comprise standardized hoses with sealable(water tight) end connectors. Thus, the rack liquid flow network canencompass 1 to N IT chassis without impacting rack topology, spaceconstraints, and without requiring unique rack manifolds. Additionally,according to one aspect, the MLD conduits are arranged in a pseudo daisychain modular configuration, which allows for unplugging of one MLDconduit from one rack level without affecting liquid flow to and coolingof other rack levels.

The system of conduits extending from node intake valve 834 into each LCnode 802 enables each LC node 802 to engage to block liquid manifold889. Block chassis 810 or node enclosure 808 of each LC node 102provides the intake and exhaust conduit connections to engage torespective terminals of MLD conduits 878 a-878 b within the MLD networkprovided by liquid rail 824. For example, where nodes 802 are designedas sleds, node enclosure 808 would be a sled tray, and each block wouldthen include more than one sled tray received into block chassis 810,forming the extensions of block liquid manifold 889. Alternatively, thenode enclosure 808 can be a single node chassis such as one of nodes 802c-802 f.

Supply and return bypass tubes 890, 891 of each block liquid manifold889 are connected by MLD conduits 878 a-878 b to form supply railconduit 830 and return rail conduit 838. Due to constraints in thespacing within the figure, the tubing that extends from supply andreturn bypass tubes 890, 891 are not shown, and the valves are shown asif connected directly to the bypass. FIG. 9 provides a more accurateview of this features of the disclosure, with conduits extended into therespective supply and return valves at each block. Also, for clarity,FIG. 8 illustrates the return rail conduit 838 separately. Liquid rail824 enables multiple types of devices to be coupled together, eachreceiving an appropriately controlled portion of cooling liquidcapacity. In one embodiment, liquid cooling subsystem 822 is passivelypressurized by attaching MLD supply conduit 892 a to facility supply 828and an MLD return conduit 892 b to facility return 840. Liquid flow fromsupply rail conduit 830 to return rail conduit 838 of liquid rail 824can be controlled based upon factors such as a temperature of the liquidcoolant, detected temperature within LC nodes 802, air temperatureinside or outside of DL RIHS 800, etc.

In an exemplary embodiment, the scalable rack manifold provided byliquid rail 824 is formed in part by MLD conduits 878 a-878 b that runvertically in the back of the RIHS 800 with quick disconnects on thefront and rear face of block liquid manifold 889 that allows forIT/infrastructure equipment respectively to be plugged into both frontand back sides of the block liquid manifold 889. For example, LC nodes802, such as server modules, can plug into the front side and fanmodules 882 can plug onto the back side of block liquid manifold 889.This also allows for other liquid cooled devices such as LC PowerDistribution Units (PDUs) to be plugged into the cooling liquid supplyrail conduit 830 and return rail conduit 838 of liquid rail 824.Thereby, a rack hot pluggable cooling interface is created for anyrack-mounted equipment.

Cooling subsystem 822 can support an embedded liquid-to-liquid heatexchanger manifold 842, such as in LC node 802 c. Node liquid-to-liquidheat exchangers are provided for rejecting heat from one fluid source toa secondary source. One aspect of the present disclosure solves theproblems that many shared-infrastructure IT systems (e.g., bladechassis) do not have adequate space to accommodate a liquid-to-liquidheat exchanger. Unlike with generally-known systems that rely uponliquid heat transfer having to exchange heat with an externalliquid-to-liquid heat exchanger, the present disclosure enables on-rackliquid-to-liquid heat exchanger that does not require any of thevertical chassis space. Additionally, the present disclosure providesthese benefits without requiring a central distribution unit (CDU),which takes up datacenter floor space. One aspect of the presentdisclosure provides embedded heat exchanger manifold 842 having a commonheat transfer plate and a shared bulk header to create a combined liquiddistribution manifold that includes a secondary liquid coolant forabsorbing heat through the shared bulk header. In particular, thecombined embedded heat exchanger manifold 842 rejects heat within sharednode enclosure 808 such as node 802 c to a secondary liquid coolant.Internal node supply 844 and return conduits 846 of a manifold built ontop of a heat exchanger core allow heat transport within manifold 842.In one embodiment, closed system pump 898 can use a first coolant tocool a high thermal energy generating functional component such as a CPUor voltage regulator.

Additionally, the liquid cooling subsystem 822 also includes afiltration system or unit 871, which prevents chemical impurities andparticulates from clogging or otherwise damaging the conduits as thefluid passes through the network of conduits. According to one aspect ofthe disclosure, liquid cooling subsystem 822 provides RFU 871 in fluidconnection with the intake pipes from facility supply 828. In at leastone embodiment, RFU 871 includes a sequenced arrangement of liquidfilters within a full-sized sled that can be removably inserted by anend user into one of the receiving slots of rack 804. In one embodiment,the RFU 871 is located on an infrastructure sled having rack-levelcontrollers and other rack-level functional components. In at least oneembodiment, the entirety of the sled is filed with components associatedwith RFU 871. Thus, it is appreciated that the RFU 871 may occupy theentire area of one vertical slot/position within the chassis. Alternatelocations of the RFU 871 can also be provided, in different embodiments,with an ideal location presenting the intake port of the RFU 871 inclose proximity to a connection to facility supply 828 to directlyreceive the facility supply 828 prior to the liquid being passed intothe remainder of the conduits of the liquid cooling subsystem 822. It isappreciated that if the system was capable of completing all heatexchange within the rack, then sealing the rack would be feasible andwould reduce and/or remove any requirements for filtration and/orallocation of rack space for RFU 871.

Liquid cooled compute systems use the high heat transport capacity ofwater. However, the disclosure recognizes and addresses the fact thatwith liquid introduced into an electronic enclosure, there is apotential for leaks that can cause catastrophic system failure. Also, insome instances, a leak can create an electronic short with a resultingexothermal reaction causing permanent damage to the DL RIHS 800. Tomitigate such risks, as one design feature, node-level carrier 893 caninclude a trench/gutter system for use as liquid containment structure894. In one embodiment, the gutter system can also incorporate anabsorbent material that can accumulate sufficient amounts of liquid fromsmall leaks to enable external sensing of the leak. Advantageously, thecarrier 893 can also be thermally conductive to serve as a heat sink forcomponents such as storage devices 895. In one embodiment, another leakdetection solution that can be incorporated into the LC node 802involves use of a solenoid to create an event when additional current isapplied, due to water pooling around the solenoid. Barriers on carrier893 can be specifically designed to contain a liquid leak and assist infunneling the liquid through the gutter system. Liquid rail 824 can alsobe provided with leak containment and detection. In one or moreembodiments, removable pipe covers 876 are sized to be mounted aroundrespective MLD conduits 878 a-878 b and can include liquid sensors 897for automatic alerts and shutdown measures.

In one or more embodiments, DL RIHS 800 further incorporates anode-level liquid containment structure 890 with a cascading drainrunoff tubing network 896 to a rack-level cascading liquid containmentstructure 894. In one or more embodiments, the DL RIHS 800 furtherincorporates leak detection response such as partial or completeautomated emergency shutdown. Liquid sensors (LS) 897 at various cascadelevels can identify affected portions of DL RIHS 800. Containment andautomatic shutoff can address the risks associated with a leakdeveloping in the DL cooling system 822.

FIG. 9A illustrates a more detailed view of DL subsystem 920 associatedwith example DL RIHS 900. Within DL RIHS 900, each LC node 902 includeschassis 910 received in a respective chassis-receiving bay 970 of rack904. Each LC node 902 contains heat-generating functional components906. Each LC node 902 is configured with a system of internal supplyconduit 944 and return conduit 946, associated with embedded heatexchanger manifold 942. Embedded heat exchanger manifold 942 receivesdirect injection of cooling liquid to regulate the ambient temperatureof LC node 902. A node-level dynamic control valve 934 and node-levelreturn check valve 936 control an amount of normal flow and provideshutoff and/or otherwise mitigate a leak. Cooling subsystem 920 providescooling to heat-generating functional components 906 inside the LC node902 by removing heat generated by heat-generating functional components906. Liquid rail 924 is formed from more than one node-to-node, MLDconduit 978 between more than one LC node 902 within in rack 904. MLDconduits 978 includes first terminal connection 983 and second terminalconnection 984. First terminal connection 983 and second terminalconnection 984 are attached on opposite ends of central conduit 985.Central conduit 985 is rack-unit dimensioned to directly mate and sealto and enable fluid transfer between a selected pair of rail supplyports 917 and/or rail return ports 919 of a selected LC node 902 and anadjacent LC node 902.

The cooling subsystem 920 includes block liquid manifolds 989 mountableat a back side of the rack 904. Each block liquid manifold has at leastone rail supply port 917 and at least one rail return port 919 on anoutside facing side of the block liquid manifold 989. The at least onerail supply port 917 and the at least one rail return port 919respectively communicate with at least one block supply port 921 and ablock return port 923 on an inside facing side of the block liquidmanifold 989. LC nodes 902 are insertable in receiving bays 970 of rack904 corresponding to locations of the mounted block liquid manifolds989. Block supply ports 921 and block return ports 923 of the LC nodes902 and an inside facing portion of the corresponding block liquidmanifold 989 are linearly aligned. The linear alignment enables directsealing, for fluid transfer, of the lineally aligned inside manifoldsupply ports 925 and return ports 927 to the inside facing portion ofthe block liquid manifold 989. In one or more embodiments, block supplyport 921 sealed to the internal manifold supply port 925 communicatesvia supply bypass tube 990 to two rail supply ports 917. Block returnport 923 sealed to internal manifold return port 927 communicates viareturn bypass tube 991 of the respective block liquid manifold 989 totwo rail return ports 919. Fan modules 982 mounted respectively ontoback of block liquid manifold 989 have apertures to expose rail supply917 and return ports 919. Additionally, fan modules 982 draw hot air 999from LC nodes 902 through an air-liquid heat exchanger 988 in blockliquid manifold 989.

In one or more embodiments, supply liquid conduit 992 a is attached forfluid transfer between facility supply 928 and rail supply port 917 ofblock liquid manifold 989 of RIHS 900. A return liquid conduit 992 b canbe attached for fluid transfer between rail return port 919 of blockliquid manifold 989 to facility return 940. FIG. 9A further illustratesthat the fluid connection to facility supply 928 includes RFU 971. Toprevent contamination or damage to cooling subsystem 920, RFU 971 isreceived in bay 970 of rack 904 and includes input port 929 connectedvia supply liquid conduit 992 a to facility supply 928. The RFU 971includes output port 931 that is connected to MLD conduit 978 of supplyrail conduit 930. Liquid rail 924 also includes return rail conduit 938.RFU 971 controls two external emergency shutoff valves 933 for flowreceived from the input port 929 that is provided via hot-pluggabledisconnects 935 to respective replaceable filtration subunits(“filters”) 937. The separation of the intake fluid across dual shutoffvalves 933 and filters 937 enables the supply of cooling liquid tocontinue even when one of the filters is removed or clogged up(preventing the passage of cooling liquid) and/or one of the shutoffvalves 933 is closed off. The cooling liquid flows in parallel to tworeplaceable filtration subunits 937, automatically diverting to theother when one is removed for cleaning or replacement. Thereby,filtration and cooling of RIHS 900 can be continuous even whileservicing one of filters 937. Back-flow is prevented by check valve 939that allows normal flow to exit to output port 931. Differentialpressure sensor 944 measures the pressure drop across filters”) 937 andprovides an electrical signal proportional to the differential pressure.According to one aspect, a Rack Liquid Infrastructure Controller (RLIC)942 can determine that one filter 937 is clogged if the differentialpressure received from differential pressure sensor 944 falls below apre-determined value.

In one or more embodiments, RIHS 900 can provide hot-pluggableserver-level liquid cooling, an integrated leak collection and detectiontrough, and an automatic emergency shut-off circuit. At a block level,RIHS 900 can provide embedded air-to-liquid heat exchange, and dynamicliquid flow control. At a rack level, RIHS 900 can providefacility-direct coolant delivery, a scalable rack fluid network, a rackfiltration unit, and automated rack flow balancing, and a service mode.

According to one embodiment, liquid rail 924 includes a series ofsecondary conduits, such as supply divert conduit 997 and return divertconduit 998 that provides a by-pass fluid path for each of MLD conduits978. In operation, divert conduit 997 allows for the removal ofcorresponding MLD conduit 978, thus removing the flow of cooling liquidto the particular block of nodes, without interrupting the flow ofcooling liquid to the other surrounding blocks of computer gear. Forexample, a particular MLD conduit 978 can be replaced due to a leak. Foranother example, a block liquid manifold 989 can be replaced. Theinclusion of divert conduits 997, 998 thus enables rapid servicing andmaintenance of block liquid manifold 989 and/or nodes within blockchassis without having to reconfigure the MLD conduits 978. In addition,the RIHS 900 can continue operating as cooling liquid continues to beprovided to the remainder of the blocks that are plugged into the liquidrail. Re-insertion of the MLD conduit 978 then reconnects the flow ofcooling liquid to the block for normal cooling operations, and shuts offthe diverted flow of cooling liquid. In an exemplary embodiment, the MLDconduits 978 provide a quick disconnect feature that interrupts flowwhen not fully engaged to a respective port 917, 919, 921, 923.Disconnection of an MLD conduit 978 interrupts flow in a primary portionof the liquid rail 924 for either supply or return, shifting flowthrough one or more divert conduits 997 to provide cooling liquid to theother block liquid manifolds 989. In one or more embodiments, a manualor active shutoff valve can interrupt flow on either or both of theprimary or divert portions of the liquid rail 924.

FIG. 9B illustrates the DL RIHS 900 having three block chasses 910, eachhaving a block liquid manifold 989 represented by a supply bypass tube990 and a return bypass tube 991. For clarity, a single LC node 902 isreceived in a respective block chassis 910. A dynamic control valve,such as a proportional valve (PV) 934, controls an amount of coolingliquid flow that is directed through an LC heat-exchange component 942to cool a functional component (FC) 906. The warmed cooling liquid flowpasses through a check valve (CV) 936 to join a bypass flow in therespective return bypass tube 991 A LC subsystem 920 provides thecooling liquid flow. Supply and divert conduits 997, 998 are notrequired to handle the flow in this nominal case with a complete liquidrail 924. FIG. 9C illustrates one LC node 920 removed. The empty blockchassis 910 provides routine bypass flow through the supply and returnbypass tubes 990, 991 as part of the primary flow path. The supply anddivert conduits 997, 998 are not required to handle the flow in asecondary path. FIG. 9D illustrates a supply MLD conduit 989 and areturn MLD conduit 989 removed for replacement. The primary flow path isinterrupted by removal of the MLD conduits 989. The supply and returndivert conduits 997, 998 provide a secondary flow path to block chasses910 that are downstream of the removed MLD conduits 989. The LC node 920that remains in the affected block chassis 910 continues to receivecooling liquid and can continue full operation. FIG. 9E illustratesremoval of a block chassis 910. The supply and return divert conduits997, 998 provide a secondary flow path to provide cooling liquid flow tothe remaining block chasses 910.

FIG. 10 illustrates a more detailed view of the internal makeup of therails and other functional components of the cooling subsystem 1022 ofexample RIHS 1000. According to one embodiment, cooling subsystem 1022also includes air movers and/or other devices to provide for forced aircooling in addition to the direct injection liquid cooling. As shown byFIG. 10, at least one fan module 1082 is rear mounted to a block liquidmanifold 1089 in which an air-to-liquid heat exchanger (or radiator)1088 is incorporated. The fan module 1082 provides air movement throughthe chassis 1010 and/or node enclosure 1008 of the node 1002 as well asthrough the air-to-liquid heat exchanger 1088. Each block liquidmanifold 1089 includes a supply bypass tube 1090 and a return bypasstube 1091 through which a dynamically determined amount of coolingliquid is directed into the respective node 1002 while allowing a bypassflow to proceed to the next node/s 1002 in fluid path of the intakeflow. Fan module 1082 includes apertures 1047 through which the supplyand return bypass tubes 1090, 1091 are extended, in one embodiment.Nodes 1002 are connected into the back side of the block liquid manifoldwith the ends of intake and exhaust liquid transfer conduits in sealedfluid connection with bypass tubes 1090 and 1091 respectively.

FIG. 11 illustrates the example DL RIHS 1000 with MLD conduits 878 a-878b (of FIG. 8) of two different multiples of rack units in dimension,according to one or more embodiments. Terminal connections 1083, 1084with connecting central conduit 1085 can be formed from hose materialswith molded perpendicular bends. FIG. 12 illustrates the example RIHS1000 including bottom-feed facility supply and return MLD conduits 1292a, 1292 b, according to one or more embodiments. FIG. 12 alsoillustrates two service buttons 1210 located at the back-lower portionof the rack. Service buttons 1210 are located on and/or in communicationwith RFU 102 k (FIG. 1), features of which are presented in greaterdetail in FIGS. 13A-13B. Service buttons 1210 enable manual triggeringof a service mode of DL RIHS, that allows for removal and re-insertionof one or more nodes and/or other components plugged into the fluid railwithout experiencing a significant amount of hydraulic force and withouthaving to shut down the entire DL RIHS to implement the service of onecomponent.

FIGS. 13A-13B illustrate additional structural details of hot pluggableRFU 1371, which includes filters for filtering out contaminants in orderto protect the liquid transfer conduits from clogging and/or chemicaldeterioration. RFU 1371 includes a front air purging connection 1303 fortemporary bleeding of pressure for filter tray installation. RFU 1371includes a rear air purging connection 1305 for temporary bleeding ofpressure for block liquid interconnect installation. RFU 1371 includeshot-pluggable filter drawer 1311 and drawer 1313 that are plumbed inparallel for continued operation during servicing of drawer 1311 ordrawer 1313. RFU 1371 includes node chassis 1308 insertable into a rackof an RIHS. At least one node supply port 1349 and at least one nodereturn port 1351 are positioned on an inserted side 1353 of the nodechassis 1308 to seal for fluid transfer respectively to a facilityliquid supply conduit and a rail supply conduit of the liquid rail of aliquid cooling system for the RIHS. First filtration subunit 1355 andsecond filtration subunit 1357 are housed in hot-pluggable filter drawer1311 and drawer 1313, which are connected in parallel fluidcommunication within node chassis 1308. Each filtration subunit 1355 andfiltration subunit 1357 is individually disengageable from node chassis1308 for maintenance or replacement, while the other filtration subunit1355 or filtration subunit 1357 remains engaged in the node chassis andcontinues liquid filtration. A liquid coolant diversion network 1359diverts liquid flow to the other filtration unit 1355 or filtration unit1357 for continuous filtration of contaminants and/or particulates fromthe cooling liquid received from the supply side, when one filtrationunit 1355 or filtration unit 1357 is removed.

FIG. 13B illustrates purge check valves 1359 that prevent liquid shortcircuit through purge solenoid valve 1310 of RFU 1371. In an exemplaryembodiment, dual node supply ports 1349 a, 1349 b and dual node returnport 1351 a, 1351 b support two independent feeds with externalsolenoids that are powered and/or controlled from RFU 1371 for filterdrawers 1311, 1313, respectively. According to one aspect, purgesolenoid valve 1310 is triggered by a rack liquid infrastructurecontroller (RLIC) or other service mode controller to open and dispensea specific amount of liquid from within the liquid cooling system ofconduits to reduce the overall pressure of liquid within the system. Inone embodiment, the amount of liquid released by purge solenoid valve1310 can be variable based on the pressure within the system of conduitsas measured by one or more liquid pressure sensors (not specificallyshown). RFU 1371 includes a differential pressure sensor that measures apressure drop across a filter and provides an electrical signalproportional to the differential pressure. According to one aspect, theRLIC can determine that the filter is clogged if the differentialpressure received from differential pressure sensor 1184C falls below apre-determined value.

FIG. 14 illustrates a method 1400 of assembling a DL RIHS, such as oneof RIHS 100, 800, 900, and/or 1000. In one or more embodiments, method1400 includes forming a block liquid manifold having a supply bypasstube and a return bypass tube that terminate respectively in a pair ofsupply ports and a pair of return ports to form a portion of a supplyconduit and a return conduit respectively of a liquid rail (block 1402).The method includes configuring a rack enclosure to receive more thanone LC nodes each configured with a system of internal conduits toreceive direct injection of cooling liquid from a liquid rail side ofthe rack chassis to regulate the ambient temperature of the node (block1404). The method 1400 includes mounting more than one LC node andcorresponding block liquid manifolds in a rack with the respectivesupply ports linearly aligned and the return ports linearly aligned,wherein the supply bypass tube and the return bypass tube of arespective block liquid manifold seals via a dynamic control valve tothe internal conduits of a corresponding LC node (block 1406). Themethod 1400 optionally includes providing selected MLD conduits in afirst number of rack units in size that can correspond to the blockchassis size and a forming selected conduits in a second number of rackunits in size, where each MLD conduit is formed having first and secondterminal connections between a central conduit (block 1408). In oneembodiment, the MLD conduits are purchased in correct dimensions from athird party supplier. The method 1300 includes attaching node-to-nodeinterconnecting MLD conduits between a selected pair of adjacent railsupply ports and adjacent rail return ports of the exterior face of theblock liquid manifolds to form a supply conduit and a return conduitrespectively of a scalable liquid rail that enables cooling to thefunctional components inside the LC nodes by enabling liquid transferthrough each node to absorb and remove heat generated by heat-generatingfunctional components inside of the node (block 1410). The methodfurther includes attaching bypass conduits across the chasses to allowfor continued flow of cooling liquid to the remaining blocks in the RIHSfollowing removal of one or more of the MLD conduits serving specificblocks along the rail. Removal of MLD conduits for a specific blockchassis can occur during servicing of one or more nodes in thatparticular block, as one example. The bypass conduits also allow thefacility supply and return to be able to connect in a reverseconfiguration, where the direction of liquid flow is reversed. Themethod 1400 includes optionally attaching a supply liquid conduit forfluid transfer to one port of one block liquid manifold of the RIHS to afacility supply and attaching a return liquid conduit for fluid transferto one port of one block liquid manifold of the RIHS to a facilityreturn (block 1412). Then method 1400 ends.

FIG. 15 illustrates a method of providing direct-interface liquidcooling of an RIHS. In one or more embodiments, the method 1500 includesselecting one of a facility supply and return and a closed loop pumpedconfiguration to move cooling liquid through a liquid rail of an RIHS(block 1502). The method 1500 includes sensing a temperature of one ormore of: a heat-generating functional component in an LC node, an airtemperature within a rack in which the LC node is mounted, an ambienttemperature outside of the RIHS, and a temperature of the cooling liquid(block 1504). The method 1500 includes filtering the supplied coolingliquid using first and second filtration subunits of the RFU (block1506). The method 1500 includes detecting when one of the filtrationunits is removed from the liquid supply (block 1508), and in response tothat detection, diverting all of the cooling liquid to filter throughthe first filtration subunit to enable continued filtration, while thesecond filtration unit is removed and/or replaced (block 1510). Themethod 1500 includes dynamically controlling a node-level supply valveto divert a portion of the cooling liquid flowing through a supplyconduit of the liquid rail through an embedded heat exchange manifoldattached in proximity to the heating-generating functional components inresponse to the sensed temperature (block 1512). The method 1500includes routing the returned cooling liquid through an air-liquid heatexchanger of a block liquid manifold to cool one of the forced coolingair and the cooling liquid before returning the cooling liquid to areturn conduit of the liquid rail (block 1514). Then method 1500 ends.

In the above described flow charts of FIGS. 14-15, one or more of themethods may be embodied in an automated manufacturing system thatperforms a series of functional processes. In some implementations,certain steps of the methods are combined, performed simultaneously orin a different order, or perhaps omitted, without deviating from thescope of the disclosure. Thus, while the method blocks are described andillustrated in a particular sequence, use of a specific sequence offunctional processes represented by the blocks is not meant to imply anylimitations on the disclosure. Changes may be made with regards to thesequence of processes without departing from the scope of the presentdisclosure. Use of a particular sequence is therefore, not to be takenin a limiting sense, and the scope of the present disclosure is definedonly by the appended claims.

One or more of the embodiments of the disclosure described can beimplementable, at least in part, using a software-controlledprogrammable processing device, such as a microprocessor, digital signalprocessor or other processing device, data processing apparatus orsystem. Thus, it is appreciated that a computer program for configuringa programmable device, apparatus or system to implement the foregoingdescribed methods is envisaged as an aspect of the present disclosure.The computer program may be embodied as source code or undergocompilation for implementation on a processing device, apparatus, orsystem. Suitably, the computer program is stored on a carrier device inmachine or device readable form, for example in solid-state memory,magnetic memory such as disk or tape, optically or magneto-opticallyreadable memory such as compact disk or digital versatile disk, flashmemory, etc. The processing device, apparatus or system utilizes theprogram or a part thereof to configure the processing device, apparatus,or system for operation.

While the disclosure has been described with reference to exemplaryembodiments, it will be understood by those skilled in the art thatvarious changes may be made and equivalents may be substituted forelements thereof without departing from the scope of the disclosure. Inaddition, many modifications may be made to adapt a particular system,device or component thereof to the teachings of the disclosure withoutdeparting from the essential scope thereof. Therefore, it is intendedthat the disclosure not be limited to the particular embodimentsdisclosed for carrying out this disclosure, but that the disclosure willinclude all embodiments falling within the scope of the appended claims.Moreover, the use of the terms first, second, etc. do not denote anyorder or importance, but rather the terms first, second, etc. are usedto distinguish one element from another.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the disclosure.As used herein, the singular forms “a”, “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the terms “comprises”and/or “comprising,” when used in this specification, specify thepresence of stated features, integers, steps, operations, elements,and/or components, but do not preclude the presence or addition of oneor more other features, integers, steps, operations, elements,components, and/or groups thereof.

The description of the present disclosure has been presented forpurposes of illustration and description, but is not intended to beexhaustive or limited to the disclosure in the form disclosed. Manymodifications and variations will be apparent to those of ordinary skillin the art without departing from the scope of the disclosure. Thedescribed embodiments were chosen and described in order to best explainthe principles of the disclosure and the practical application, and toenable others of ordinary skill in the art to understand the disclosurefor various embodiments with various modifications as are suited to theparticular use contemplated.

What is claimed is:
 1. A Rack Information Handling System (RIHS)comprising: a rack having chassis-receiving bays; more than one liquidcooled (LC) node each comprising a chassis received in a respectivechassis-receiving bay of the rack and containing heat-generatingfunctional components, each LC node configured with a system of conduitsto receive direct injection of cooling liquid to regulate the ambienttemperature of the node and provide cooling to the functional componentsinside the node by removing heat generated by the heat-generatingfunctional components; and a cooling subsystem having a liquid railformed by more than one node-to-node, Modular Liquid Distribution (MLD)conduit between LC nodes provisioned in the rack and comprising firstand second terminal fluid connections attached on opposite ends of acentral conduit to seal to and enable fluid transfer between a port of aselected LC node and a port of another adjacent node.
 2. The RIHS ofclaim 1, wherein the MLD conduits are provided in rack-unit dimensionsto selectively support LC nodes of selected rack-unit vertical heights.3. The RIHS of claim 1, further comprising a plurality of block liquidmanifolds mountable at a back of a rack, where each block liquidmanifold has two supply ports and two rail return ports on an outsidefacing side of the block liquid manifold that respectively communicatewith at least one manifold supply port and a manifold return port on aninside facing side of the block liquid manifold, wherein the more thanone LC nodes are insertably placed in receiving bays of the rackcorresponding to locations of the mounted block liquid manifolds, withblock supply ports and block return ports of the LC nodes and an insidefacing portion of the corresponding block liquid manifold linearlyaligned, and sealing, for fluid transfer, the block supply and returnports of a selected one or more LC nodes to the lineally alignedmanifold supply and return ports of the inside facing portion of theblock liquid manifold, each block liquid manifold comprising a supplybypass tube that communicates a bypass supply flow between the two railsupply ports with a node-selected portion of the bypass supply flowdiverted from the manifold supply port to the block supply port, eachblock liquid manifold comprising a return bypass tube that communicatesa bypass return flow between the two rail return ports with thenode-selected portion of the bypass supply flow diverted after routingthrough the respective LC node from the block return port to themanifold supply port.
 4. The RIHS of claim 3, wherein: the first andsecond liquids ports of the supply bypass tubes are linearly aligned;and the first and second liquid ports of the return bypass tubes arelinearly aligned.
 5. The RIHS of claim 3, wherein the node liquidmanifold comprises an air-liquid heat exchanger that receives liquidflow from the liquid rail that transfers heat from airflow through theattached LC node into the liquid flow.
 6. The RIHS of claim 3, furthercomprising: a modular liquid supply component attachable between aselected port of a supply bypass tube of the liquid rail and a liquidsupply; and a modular liquid return component attachable between aselected port of a return bypass tube of the liquid rail and a liquidreturn.
 7. The RIHS of claim 3, wherein the MLD conduits form a closedloop between a supply side and return side of the liquid rail, the RIHSfurther comprising a fluid mover to create a fluid flow through theclosed loop.
 8. The RIHS of claim 3, further comprising a fan moduleattachable to the block liquid manifold and comprising one or more airmovers positioned to move air through the air-liquid heat exchanger andcomprising an opening to expose the first and second ports of the supplyand return bypass tubes to enable assembly with the block liquidmanifold.
 9. The RIHS of claim 1, wherein the liquid rail comprises adivert conduit connected for a secondary flow path across at least aportion of the liquid rail to supply cooling liquid to at least one nodein response to disconnection of an MLD conduit that interrupts a primaryflow path.
 10. A cooling subsystem of a direct-interface liquid-cooled(DL) Rack Information Handling System (RIHS), the cooling subsystemcomprising: a liquid rail formed by more than one node-to-node, ModularLiquid Distribution (MLD) conduit between more than one liquid cooled(LC) node provisioned in a rack and comprising: first and secondterminal fluid connections attached on opposite ends of a centralconduit to seal to and enable fluid transfer between a port of aselected LC node and a port of an adjacent LC node, wherein each LC nodecomprising a chassis received in a respective chassis-receiving bay ofthe rack and containing heat-generating functional components, each LCnode configured with a system of conduits to receive direct injection ofcooling liquid to regulate the ambient temperature of the node andprovide cooling to the functional components inside the node byabsorbing and removing heat generated by the heat-generating functionalcomponents inside of the LC node.
 11. The cooling subsystem of claim 10,wherein the MLD conduits are provided in rack-unit dimensions toselectly support LC nodes of selected rack-unit vertical heights. 12.The cooling subsystem of claim 10, further comprising a plurality ofblock liquid manifolds mountable at a back of a rack, where each blockliquid manifold has two supply ports and two rail return ports on anoutside facing side of the block liquid manifold that respectivelycommunicate with at least one manifold supply port and a manifold returnport on an inside facing side of the block liquid manifold, wherein themore than one LC nodes are insertably placed in receiving bays of therack corresponding to locations of the mounted block liquid manifolds,with block supply ports and block return ports of the LC nodes and aninside facing portion of the corresponding block liquid manifoldlinearly aligned, and sealing, for fluid transfer, the block supply andreturn ports of a selected one or more LC nodes to the lineally alignedmanifold supply and return ports of the inside facing portion of theblock liquid manifold, each block liquid manifold comprising a supplybypass tube that communicates a bypass supply flow between the two railsupply ports with a node-selected portion of the bypass supply flowdiverted from the manifold supply port to the block supply port, eachblock liquid manifold comprising a return bypass tube that communicatesa bypass return flow between the two rail return ports with thenode-selected portion of the bypass supply flow diverted after routingthrough the respective LC node from the block return port to themanifold supply port.
 13. The cooling subsystem of claim 12, wherein:the first and second liquids ports of the supply bypass tubes arelinearly aligned; and the first and second liquid ports of the returnbypass tubes are linearly aligned.
 14. The cooling subsystem of claim12, wherein the node liquid manifold comprises an air-liquid heatexchanger that receives fluid flow from the liquid rail that transfersheat from airflow through the attached LC node into the fluid flow. 15.The cooling subsystem of claim 12, further comprising: a modular liquidsupply component attachable between a selected port of a supply bypasstube of the liquid rail and a liquid supply; and a modular liquid returncomponent attachable between a selected port of a return bypass tube ofthe liquid rail and a liquid return.
 16. The cooling subsystem of claim12, wherein the MLD conduits form a closed loop between a supply sideand return side of the liquid rail, the RIHS further comprising a fluidmover to create a fluid flow through the closed loop liquid rail. 17.The cooling subsystem of claim 12, further comprising a fan moduleattachable to the block liquid manifold and comprising one or more airmovers positioned to move air through the air-liquid heat exchanger andcomprising an opening to expose the first and second ports of the supplyand return bypass tubes.
 18. The cooling system of claim 10, wherein theliquid rail comprises a divert conduit connected for a secondary flowpath across at least a portion of the liquid rail to supply coolingliquid to at least one node in response to disconnection of an MLDconduit that interrupts a primary flow path.
 19. A method of assemblinga Direct-Interface Liquid-Cooled (DL) Rack Information Handling System(RIHS), the method comprising: mounting a plurality of block liquidmanifolds at a back of rack, where each block liquid manifold has atleast one rail supply port and a rail return port on an outside facingside of the block liquid manifold that respectively communicate with atleast one block supply port and a block return port on an inside facingside of the block liquid manifold; inserting more than one LC nodes inreceiving bays of the rack corresponding to locations of the mountedblock liquid manifolds, with the block supply ports and the block returnports of the LC nodes and an inside facing portion of the correspondingblock liquid manifold linearly aligned; sealing, for fluid transfer, theports of a selected one or more LC nodes to the lineally aligned blocksupply and return ports of the inside facing portion of the block liquidmanifold; and attaching node-to-node interconnecting Modular LiquidDistribution (MLD) conduits between a selected pair of adjacent railsupply ports and adjacent rail return ports of the exterior face of theblock liquid manifolds to form a supply conduit and a return conduitrespectively of a scalable liquid rail that enables cooling to thefunctional components inside the LC nodes by enabling liquid transferthrough each node to absorb and remove heat generated by heat-generatingfunctional components inside of the node.
 20. The method of claim 19,further comprising forming the block liquid manifold by: forming asupply bypass tube and a return bypass tube that, with the MLD conduits,provides the liquid rail, each of the supply and return bypass tubesterminating in first and second ports that connect to a respective MLDconduit to form a portion of one of the supply conduits and returnconduits of the liquid rail.
 21. The method of claim 20, furthercomprising attaching a supply liquid conduit for fluid transfer to onerail supply port of one block liquid manifold of the RIHS to a facilitysupply and attaching a return liquid conduit for fluid transfer to onerail return port of one block liquid manifold of the RIHS to a facilityreturn.
 22. The method of claim 19, further comprising: assembling morethan one Liquid Cooled (LC) node by: provisioning heat-generatingfunctional components in an enclosure of an LC node that has a verticalheight that is one of a plurality of multiples of rack units, andconfiguring the enclosure with a system of internal conduits to receivedirect injection of cooling liquid from a liquid rail side of thechassis to regulate the ambient temperature of the node; assembling aportion of the liquid rail corresponding to a vertical location of theLC node using a selected MLD conduits having a number of rack units inheight that correspond to the height of the LC node to laterally alignwith the supply and return ports of the LC node and an adjacent LC node.23. The method of claim 19, further comprising: attaching a divertconduit across at least a portion of the liquid rail to provide asecondary flow path to supply cooling liquid to at least one node inresponse to disconnection of an MLD conduit that interrupts a primaryflow path.